Today: Google attempts to bolster its streaming-music offerings with Songza, part of a wave of music interest that has included Apple's Beats purchase and Twitter's reported interest in SoundCloud. Also: New record highs for Wall Street, Netflix.

The Lead: Google acquires Songza to boost streaming music offerings

Google dipped a toe into the boiling-hot waters of streaming-music services Tuesday, picking up curation app Songza as tech giants and startups battle for mobile music consumers.

"Over the coming months, we'll explore ways to bring what you love about Songza to Google Play Music," a Google+ post on the acquisition read. "We'll also look for opportunities to bring their great work to the music experience on YouTube and other Google products."

Streaming music has not proved to be a profitable business, and presents difficult licensing rights: Oakland-based Pandora Media, the largest Silicon Valley public company focused solely on streaming music, is involved in a numberof legaland closed-door fights on music-licensing rights and has yet to turn an annual profit. But Pandora's total revenues continue to grow, topping $600 million in 2013, and consumer-facing companies such as Google, Apple and Twitter realize the broad reach mobile music brings.

"Clearly, tech firms such as Google, Apple and Amazon are placing big bets that music will eventually pay dividends as part of a broader digital content strategy." eMarketer analyst Paul Verna said in an email.

EMarketer estimates that online and mobile radio advertisements generated $1.65 billion in the United States in 2013, with an increase to more than $2 billion expected this year -- roughly 10 percent of Google's expected U.S. online ad revenues. Google could go bigger if it wants to keep spending on digital music: The Mountain View company revealed recently that it plans to spend up to $30 billion on foreign acquisitions, and one of the most popular music-streaming services -- Spotify, valued at $4 billion -- is based in Europe.

Google stock increased 1.2 percent to $591.49 Tuesday, and gained slightly in after-hours trading following its announcement of the purchase.